1. Heat the Oven & Prepare the Crust:
Preheat your oven to 400°F (204°C). Place the unbaked pie crust into a 9-inch pie dish and crimp the edges as desired.
2. Assemble the Filling, Layer by Layer:
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Carefully pour the 1½ cups of water directly into the pie crust.
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In a separate bowl, whisk together the sugar, flour, and salt. Sprinkle this dry mixture evenly over the surface of the water. Do not stir.
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Scatter the pieces of cold butter evenly over the top.
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Drizzle the vanilla extract over everything.
 
3. Bake the Pie:
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Place the pie in the preheated oven and bake at 400°F (204°C) for 30 minutes.
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Without opening the oven door, reduce the temperature to 375°F (190°C) and continue baking for another 30 minutes. The pie is done when the top is a deep golden brown and the filling is set with a slight jiggle in the center.
 
5. Serve and Enjoy:
Once fully cooled, slice and serve. Enjoy this taste of history as is, or with a dollop of whipped cream for a touch of indulgence.
A Note on the Magic
The genius of this pie lies in its layered, unstirred method. As it bakes, the ingredients separate and transform. The flour and sugar sink to form a sweet, caramelized base, while the butter melts into the top to create a rich, crisp layer. It’s a beautiful example of kitchen science from a bygone era.